PHILADELPHIA (CBS) — A new investigation is shining light on those five-star reviews on Amazon. It says the site is flooded with thousands of fake five-star reviews, according to the British watchdog group Which.

It says many products have unverified reviews, meaning there was no proof the person writing the review actually bought the item. Which says consumers should be suspicious of a large number of reviews that contain similar language or phrases.

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Also, go with brands that are household names, or brands that you recognize. Which also recommends using Fakespot to scan the reliability of a review by copying and pasting the URL into their search bar.